Thailand’s repeated coups have elicited only muted protests internationally so far. A 2013 academic paper attributes this to four factors, with one being Washington’s traditional support for the Thai monarchy, which is close to Thailand’s military. However, proceedings at a recent US congressional hearing on the May 22 coup suggest this could change.

The US has already suspended a USD 4.7-million security assistance to this ASEAN nation, and excluded it from the US-hosted Rim of the Pacific Exercise, the largest international maritime warfare drill.

Washington’s assistance to Bangkok over the past three years – USD 8 million spent on armed combat training and defence upgrade – has also been questioned, and if critics at Capitol Hill have their way, the US-funded Cobra Gold military exercise, the largest in Asia-Pacific, could be moved to Australia from Thailand.

One of the most scathing criticisms came from Scot Marciel, senior US diplomat for East Asian and Pacific Affairs, who said it was unlikely “the coup and subsequent repressive actions will produce the political compromise and reconciliation that Thailand so desperately needs“.

“The coup and post-coup repression have made it impossible for our relationship with Thailand to go on with ‘business as usual’,” Marciel said in his testimony before the House Committee on Foreign Affairs in Washington on June 24. “We continue to review other programmes and engagements, and will consider further measures as circumstances warrant,” he added.

In Luxembourg, the 28-member European Union announced it was shelving a proposed economic agreement with Thailand, saying the army’s recent announcement “falls short of the credible roadmap” for a return to constitutional rule. The agreement had been planned for July.

“Against this background, the EU is forced to reconsider its engagement,” it said on June 23. “Official visits to and from Thailand have been suspended; the EU and its member states will not sign the Partnership and Cooperation Agreement with Thailand, until a democratically elected government is in place.”

Coup leaders are now on damage-control mode. A senior army official, Lt Gen Chatchalerm Chalermsukh, told BBC that the coup was not planned but goaded by protracted civil unrest. “So far as I know, there was no advanced planning,” he told BBC. “If it were planned that would be illegitimate.”

However, Suthep Thaugsuban, a leader of anti-government demonstrations, has publicly said he and the Thai Army chief Prayuth Chan-ocha have been planning the purge for four years.

In a paper published in the Australian Journal of International Affairs, research scholar Nicholas Farrelly says Thailand’s leading figures including royal family members are reluctant to embrace democratic processes, and consequently dislike deposed Prime Minister Yingluck Shinawatra and her exiled brother Thaksin, also a former prime minister, who enjoy rural support.

US diplomat Marciel said it was important that the transition to democracy was inclusive, transparent and achieved through fair elections. At the same time, he expressed doubts of this happening soon. “The current military coup is both more repressive and likely to last longer than the last one,” he told the congressional hearing.